physiology

Question 1

what occurs when local electrical change triggers a wave of excitation that travels along the muscle fiber

Answer 1

conductivity

Question 2

what is the capability of being stretched between contractions

Answer 2

extensibility

Question 3

how does muscle attach to bone

Answer 3

via tendons

Question 4

what is connective tissue around muscle cells

Answer 4

endomysium

Question 5

what is connective tissue around muscle fascicles

Answer 5

perimysium

Question 6

what is connective tissue surrounding entire muscle

Answer 6

epimysium

Question 7

where does regulation of calcium for muscle fibers occur

Answer 7

sarcoplasmic reticulum

Question 8

what is the plasma membrane of a muscle fiber

Answer 8

sarcolemma

Question 9

what is the cytoplasm of a muscle fiber

Answer 9

sarcoplasm

Question 10

what is the filamentous proteins which provide structure and contractile capacity to muscle

Answer 10

myofilaments

Question 11

what are large intracellular bundles of contractile protein myofilaments

Answer 11

myofibrils

Question 12

what are the tubular invaginations of the sarcolemma which penetrate through the cell and emerge on the other side; essential for calcium release from cisternae

Answer 12

transverse tubules

Question 13

what is the thick filament primary made of

Answer 13

myosin

Question 14

what is the thin filament mostly made of

Answer 14

actin

Question 15

describe the protein of myosin

Answer 15

it is a hexametric protein, composed of 2 heavy chain polypeptides and 4 light-chain polypeptides

Question 16

what are the 3 functions of the myosin sub fragment-1(S-1)

Answer 16

attachment site for actin to form actomyosin linkages (cross bridges), binding site for adenosine nucleotides, ATPase enzymatic region for hydrolysis of ATP

Question 17

what is actomyosin complex formation triggered by

Answer 17

calcium

Question 18

what filaments are in the H band

Answer 18

thick

Question 19

what filaments are in the I band

Answer 19

thin

Question 20

what is the segment of the myofibril from one z disc to the next

Answer 20

sarcomere

Question 21

what is the functional contractile unit of the muscle fiber

Answer 21

sarcomere

Question 22

what type of potential occurs in the cell body

Answer 22

local potential (has to do with chemical release)

Question 23

how many neurons is each somatic motor fiber innervated by

Answer 23

one motor neuron

Question 24

how many fibers does one alpha motor neuron have

Answer 24

typically many

Question 25

are alpha motor neurons typically associated with extrafusal or intrafusal fibers

Answer 25

extrafusal fibers

Question 26

are gamma motor neurons typically associated with

Answer 26

intrafusal

Question 27

what is the average motor unit

Answer 27

200 muscle fibers for each motor unit

Question 28

what type of fibers does the muscle spindle receptor have

Answer 28

1a

Question 29

what type of fibers does the golgi tendon organ have

Answer 29

1b

Question 30

what type of receptors does the free nerve endings have

Answer 30

3 or 4

Question 31

what type of receptors are nuclear chain fibers most associated with

Answer 31

steady-state (tonic) receptors

Question 32

what type of receptors are nuclear bag fibers most associated with

Answer 32

adapting (phasic;dynamic) receptors

Question 33

what is the function of muscle spindles

Answer 33

to inform the CNS of muscle length and dynamic movements

Question 34

what part of intrafusal fibers cannot contract

Answer 34

the middle of the fiber because it lacks sarcomeres

Question 35

what is another name for the primary afferent neuron

Answer 35

group 1a

Question 36

what is another name for the secondary afferent neuron

Answer 36

group 2

Question 37

where do gamma motoneurons originate

Answer 37

in the anterior horn of the spinal cord

Question 38

what is the stretch reflex primarily mediated by

Answer 38

the brain

Question 39

what type of reflex is the golgi tendon organ

Answer 39

clasp knife

Question 40

what type of fibers does the golgi tendon organ have

Answer 40

1b